Weldrod and process of welding



Patented Dec. 31, 1935 PATENT OFFICE Q WELDROD PROCESS OF WELDING John Howe Hall, High Bridge, N. 'J., assignor to Taylor-Wharton Iron & Steel Company, High Bridge, N. J a corporation of New Jersey No Drawing.

Application August 8, 1930, Serial No. 474,069 a V Y 7 Claims. (01. 219-10) 7 The invention relates to weldrods and processes for both electric arc and gas welding and, while usable with excellent results in the joining of ordinary steel plates, was devised principally for use, and has achieved outstanding results, in the welding of plates or. structures containing from ten to fifteen percent manganese. More specifically, the invention finds its chief utility in the repairing of manganese steel castings and l forgings, as, forexample, in the building up or restoring, by weld deposit metal, of the badly worn surfaces of special trackwor-k, such as manganese steel frogs and crossings, switches and the like, and in' repairing, by weld deposit metal, the broken or otherwise damaged areas 25 ing, the transition area or partially fused zone between the deposited metal and the unaffected parent metal is made weak and brittle by the "heating and partial fusion to ,which it is sub- Jected. This embrittlement and loss of strength is due to the liberation ofcarbides in and between the austenite crystals of the metal, and the strength and toughness of the steel so affected can be only partially restored by heattreatment.

After extended experimentation and study I have concluded that the liberation of carbides with its resultant brittleness and weakness is due to the relatively high carbon content of the parent metal, viz. 1.10 to 1.40%. Hence, in one aspect my invention consists in obviating or materially reducing the liberation of carbides by diluting the carbon of the partially fused or transition zone. In another aspect my inven- 45 tion consists in impregnating the transition zone with nickel to make it susceptible to air toughening and to avoid conditions making for burning. I

In short, the objects of the invention are to 50 provide for first-class weldability regardless of the source of heat for depositing the weld metal; and to insure welds of high tensile strength and ductility.

In accordance with my inventive thought I use a weldrod containing ten to fifteen per cent manganese, one to five per cent nickel, about decimal thirty to about decimal eighty-five per cent carbon, and an effective amount of silicon; the preferred composition being an iron or steel alloy containing thirteen per cent manganese, three per cent nickel, decimal seventy-five per cent carbon and from decimal fifteen to two decimal five percent silicon. The higher the silicon content, within the range stated, the bet ter the insurance of realizing the ultimate object of soundness of weld notwithstanding that de- 10 pendence is had on the air toughening properties of the metal of the weld. The relatively high content of silicon enables the steel to dissolve a high pro-port'on of the gases which cause blow holes. One of the contributory factors to the accomplishment of this result is that the silicon reduces the oxides of iron and manganese present, forming SiOz which goes into. the slag, so that with less oxide of manganese and of iron present there is less tendency to the formation of CO gas when the steel solidifies by the reaction between the carbon of the steel and such oxides. The silicon, therefore, is important in that it has both a direct and indirect eifect in preventing the formation of blow holes and, hence, makes for sound ste'el. A high silicon content is of utility in substantially eliminating the formation of slag and scale, thereby insuring greater fluidity of the weld depositing metal. The ideal range of silicon content is from about one decimal twenty-five to about one decimal sixty per cent. Moreover, the high silicon content, such as indicated, lessens the cost of production of the air toughening steel.

In most cases the desired composition in the deposited metal is secured by using a rod of the above analysis. However, I do not restrict myself to the use of such a rod, as one or more of the constituents-manganese, nickel, carbon, and silicon may be introduced in the deposited metal by using rods containing some of these constituents, which have been coated with materials containing a high percentage of some of the other constituents, in the well-known or 5 conventional manner.

Thus, for instance, a rod containing ten to fifteen per cent manganese, decimal thirty to one per cent carbon, and one decimal five per cent silicon may be coated with a ferro-nickel or metallic nickel in suflicient amount to give the desired percentage of nickel in the deposited metal. The same may be done in the case of the manganese and the silicon by using coatings containing ferro alloys of high percentages of thesselementaortheseeiementsinthemetaliicstate.

8imilarly,partoralloftbecarbonmaybe containedinthemetalsoralloyssousedasa coating. It ispossiblealsotoaddthe nickel, the

manganese, thesilicon,orthe carbontothepool of deposited metal while it is still in the fiuid condition. The merit of the invention consists in securing a deposited metal of the correct composition, and the scope of this invention is not tobelimitedto anyone methodof securing the desired composition in the deposited metal.

The effect ofthe low percentage of carbon in the deposit metal is, as before stated. to dilute the relatively high carbon content of the partially fused or transition zone of the parent alternating or direct current.

Having described-my invention, I claim: l. The method of-.restoring worn surfaces or repairing. otherwise damal parts of articles constructed of ferrous alloys containing ten to fifteen per centand one to one decimal four per cent carbon, more or less which consists in nonecarbide metal.

ammo: producing sound welds in ructed often percent in effecting a weld deposit of metalcontaining tofifteenpercentmanganesaonetofive centnickel,andalesspercentageofcarbon .thantheparent stoekforthepurposeandwith .the result 'ot diluting the relatively h i carbon ontent of the partially fused or transition sone andofsubstantiaily reducing the liberationof s. m n mes s: ductile weld'of manganese-steelcontaining one to one decimal four per cent carbon, which consists in welding by depositing manganese steel having air toughening properties and a lower percentage of carbon than that of the parent stock in order to dilute the carbon of the parent stock and thereby obviate conditions tending to embrittlement and loss of strength and toughness.

4. The method of producing sound welds of manganese steel. that is to say, iron or steel alloy containing ten to fifteen per cent nose and from substantially one to one decimal 10 four per cent carbon, which consists in welding by depositing ferrous metal containing ten to fifteen per cent manganese, nickel in sufl cient amount up to about five per cent to insure air toughening and an essentially lower carbon content than that of the parent stock whereby the carbon content of the parent stock is diluted and the nickel impregnates the partially fused or transition zone and makes it responsive 'to air toughening. go 5. The method of producingsound welds of articles constructed or iron or steel alloys containing ten to fifteen per cent manganese and substantially one to. one decimal four per cent carbon, which consists ineifecting a fusion weld as with an ironor steel alloy containing ten to fifteen per cent manganese. one to five per cent nickel, and a carbon content materially less than that of the parent stock for the purpose and with the result of dilut ng the carbon content of the so partially fused or transition zone.

6. The method for re-surfacing or otherwise repairing austenitic manganese steel articles which contain carbon in sufliciently high amount to liberate carbides and cause embrltl5 tlement under ordinary conditions of weld deposit, which consists in depositing manganese steel having airtoughening properti s. a carbon content essentially lower than that of the parent stock inorder to minimize carbide precipitation. 40 andsuflicient silicon to keep the pool quiescent and permit substantial dilution of the carbon in the transition zone. a

"I. for re-surfacing or otherwise pairing austenitic manganese steelarticles which to contain carbon in .suflciently high amount to liberate carbides and run the hazard of embrittle- 'mentunder ordinary conditionsoof welding. said rod containing manganese substantially in the proportionof that of the article, a proportion- 60 ately lower rate of carbon to minimize carbide precipitation, not over five per cent nickel to impart air; toughenin properties to the transi-' tion none of the parent metal, and silicon in sufiicient amount up to two decimal seventy-five to prevent gasifying.

JOHN HOWE. HALL. 

